Heart Health in Midlife Linked to Future Dementia Risk

A recent study has revealed a significant connection between heart health in midlife and the risk of developing dementia later in life. Researchers from University College London conducted the study, which was published in the European Heart Journal, highlighting that individuals exhibiting signs of heart damage while in their middle years may face an increased likelihood of dementia as they age.

The study focused on the presence of a protein known as cardiac troponin I, found in the bloodstream when heart muscle sustains damage. Researchers observed that middle-aged individuals with elevated levels of this protein showed a higher propensity for developing dementia, with the correlation evident up to 25 years before a formal diagnosis. Troponin levels are typically monitored in patients suspected of experiencing a heart attack, but this study suggests that even mildly elevated levels without any symptoms could indicate underlying heart issues, potentially affecting overall brain health.

According to Professor Eric Brunner from the UCL Institute of Epidemiology and Health Care, “Poor heart health in middle age puts people at increased risk of dementia in later life.” He emphasized that the damage to the brain associated with dementia accumulates gradually over decades before symptoms emerge. Professor Brunner highlighted the importance of managing common risk factors for both heart disease and dementia, such as high blood pressure, to potentially mitigate the development of these conditions.

Study Insights and Findings

The research involved nearly 6,000 participants from the long-term Whitehall II study, which has tracked British Civil Service employees since 1985 to investigate aging and health. Participants, aged between 45 and 69, underwent high-sensitivity troponin testing, which measures lower troponin levels than those typically assessed during a heart attack. At the time of the initial blood tests, none of the participants had been diagnosed with dementia or cardiovascular disease.

Over the course of an average follow-up period of 25 years, 695 participants were diagnosed with dementia. When comparing those with dementia to those without, researchers found that individuals diagnosed with dementia consistently exhibited higher troponin levels in their blood. Notably, participants with the highest levels of troponin at the study’s beginning had a 38% increased risk of developing dementia by the end of the follow-up period.

Moreover, the study revealed that elevated troponin levels in middle-aged individuals were associated with faster cognitive decline. Adjusted for factors such as sex, ethnicity, and educational background, participants with higher troponin levels demonstrated a decline in memory and problem-solving abilities that corresponded to cognitive performance levels of individuals nearly a year and a half older by the age of 80.

Implications for Future Research and Health Recommendations

The researchers also examined a subgroup of 641 individuals from the Whitehall II study who had undergone MRI scans of their brains. The findings indicated that those with higher troponin levels had smaller hippocampi—a brain region vital for memory—15 years later, along with decreased gray matter volume, which is crucial for information processing. The brain scans suggested that the cognitive profiles of participants reflected those of individuals approximately three years older.

Lead author Dr. Simon Chen noted, “Our study represents the longest follow-up to date to investigate links between raised cardiac troponin levels, cognitive decline, and dementia.” He added that the data suggests midlife troponin levels may serve as a more reliable biomarker for predicting dementia risk.

The study has garnered attention from health organizations, including the British Heart Foundation. Professor Bryan Williams, Chief Scientific and Medical Officer at the foundation, stated, “This study is an important reminder that our heart and brain health are inseparable.” He advised that maintaining heart health throughout life provides the best opportunity for healthy brain aging. This includes managing blood pressure, cholesterol levels, maintaining physical activity, achieving a healthy weight, and avoiding smoking.

This comprehensive study underscores the significance of cardiovascular health in midlife as a critical factor in reducing the risk of dementia in later years, highlighting the need for further research to establish troponin levels as a predictive tool for dementia risk.